That would not be the story but a non-canon crossover like Kingdom Hearts that has some "canon-like" elements in it (like the Warrior of Light walking to Cornelia at the end of Dissidia to show the beginning of Final Fantasy - "And so their journey begins" but without the three other characters). I am talking about Final Fantasy XIII itself. It just does not need to be called "Sexy Workout with Lightning" or anything. Not that I mind though, I like the Sexy Workout Edition that Final Fantasy XIII-3 is.